Index commutator means for oscillating barrels

ABSTRACT

A galvanizing device comprising a pivoted drum to hold workpieces, means for rocking the drum to a limited extent, a carrying frame in which the drum is pivoted, pierced longitudinal walls of plastics material within the drum the cross-section of the walls being partially heart-shaped, longitudinal strengthening bars attached to the walls and to the ends of the drum, the bars carrying partially exposed current-carrying contact rods, and connections from the rods to a low-voltage high current electric supply. The drum dips into a vat containing treatment liquid which penetrates the holes in the walls and contacts the workpieces in the drum.

United States Patent 1 Ziebarth et al.

[54] INDEX COMMUTATOR MEANS FOR OSCILLATING BARRELS [75] Inventors: Paul E. Ziebarth, Hillegossen; Reinhold Ritter, Herford-Elverdissen,

both of Germany [73] Assignee: Langheim & Co., Heepen b.

Bielefeld, Germany [22] Filed: May 20,1971

21 Appl. No.: 145,254

[30] Foreign Application Priority Data Feb. 11, 1971 Germany ..P 21 06 544.1

[52] US. Cl. ..204/213, 204/222: 259/89. [51] Int. Cl. ..C23b 5/78 [58] Field oi Search ..204/213-214, 222-223; 259/89-90; l34ll59-164 [56] 7 References Cited UNITED STATES PATENTS 2,830,946 4/1958 Pleadwell ..204/214 X 1 Mar. 27, 1973 Primary Examiner-John H. Mack Assistant Examiner-Regan J. Fay Attorney-Leonard H. King [57] ABSTRACT A galvanizing device comprising a pivoted drum to hold workpieces, means for rocking the drum to a limited extent, a carrying frame in which the drum is pivoted, pierced longitudinal walls of plastics material within the drum the cross'section of the walls being partially heart-shaped, longitudinal strengthening bars attached to the walls and to the ends of the drum, the bars carrying partially exposed current-carrying contact rods, and connections from the rods to a low-voltage high current electric supply. The drum dips into a vat containing treatment liquid which penetrates the holes in the walls and contacts the workpieces in the drum.

12 Claims, 8 Drawing Figures INDEX COMMUTATOR MEANS FOR OSCILLATING BARRELS PRIOR APPLICATIONS In Federal Republic of Germany on Feb. 11, 1971 and numbered P 21 06 544.1

The invention relates to a galvanizing device with a pendulum drum which holds workpieces to be galvanically surface-treated. It is mounted so as to be pivotable to and fro in a carrying frame, and is equipped with openings in the side of the casing for the passage of a galvanizing liquid.

Pendulum drums for galvanizing devices have been known in various designs and shapes of cross-section, most known drums have the disadvantages of intricate construction and costly manufacture. Furthermore, known drums permit only a comparatively small current consumption, which necessitates a long period of treatment of the workpieces.

The object of the present invention is the production of an improved galvanizing device with a pendulum drum which is simple, stable and long-lasting, and enables a high input current to be used.

According to the present invention there is provided a galvanizing device comprising a pendulum drum which accepts workpieces to be treated, the drum defining perforations to allow passage of the galvanizing liquid, a carrying frame in which the pendulum drum is mounted, so as to be pivotable to and fro, plastics material wall parts within the pendulum drum the section of the wall parts being part heart-shaped and defining a filling and emptying aperture, longitudinal strengthening bars to which said wall parts are fastened as by welding, a contact rod part-enclosed by each said bar, connections from said rods to a current supply and end walls which close the drum, said wall parts and strengthening bars being also fastened to said end walls.

An embodiment of the invention is shown in the accompanying drawings, in which:

FIG. 1 shows a perspective view of an electroplating device with a pendulum drum mounted in a carrying frame, and a liquid bath container with a carrying frame in a position in which it is lifted out of the container;

FIG. 2 shows a cross-section through the pendulum drum, which is made from several parts and has a heartshaped cross-section with contact bars and a contact part fastened to the front of the drum;

FIG. 3 shows a longitudinal section through the pendulum drum which is suspended by its carrying frame in the treatment bath container, has a motor driven gear for the pendulum drum, contact parts which are fastened to the end of the pendulum drum, and a lead to a conductor rail on the carrying frame, as well as an index ring which is fastened about a bearing of the drum, and co-operates with a contact device which is arranged on the container;

FIG. 4 shows a section at point A in FIG. 3 of the conducting connection between the contact bar mounted inside the pendulum drum and an outer contact part mounted in the front of the drum;

FIG. 5 shows a section at point B" in FIG. 3 of the contact part with a connecting piece and a lead fastened to it;

FIG. 6 shows a section at point C in FIG. 3 of the connection of two cathode rods which form a contact bar inside the pendulum drum;

FIG. 7 shows an end view of a pendulum drum hav ing an index ring which has small metal plate contacts, a control device on the treatment bath container, and with two initiators, in a pivoted position of the drum; and

FIG. 8 shows an end view of the index ring of FIG. 7 in an inverse pivotal position.

A plating device of the invention for the galvanic surface treatment of merchandise (shaped parts) possesses a pendulum drum 12, which is mounted so as to be pivotable to and fro in a carrying frame 10, and defines openings 11 on the side of the casing for the passage of a medium, the drum being rotatably and detachably supported in the carrying frame 10 by means of two facing bearings 13 which form a pivotal axis.

The pendulum drum 12 shows in cross-section several wall parts 15 and 16, connected together to form an incomplete heart shape, with a filling and emptying aperture 14, the wall parts 15 have cross-sections which are annular, and the wall parts 16, in cross-section, are part curved, part straight.

Adjacent wall parts 15 and 15, as well as 15 and 16 are connected together by a common strengthening bar 19 which simultaneously forms a support 17 for a contact bar 18, which is partly enclosed therein, and is connected to a current supply. The individual wall parts 15 and 16 of the drum 12 are fastened by welding to the strengthening bars and by welding to end plates 20, which terminate the drum 12 at each end.

To facilitate a welded connection between wall parts 15 and 16, and strengthening bars 19, the edge regions of the wall parts 15 and 16 fit in channels 21 of the strengthening bars 19, which are preferably formed as extrusion profiles.

Each strengthening bar 19, which has a circular, angular, or oval cross-section, defines a recess 17 over the entire length of the bar, which is the same shape as the cross-section of the contact bar 18. There is a channel 21 on both sides of this recess to receive wall parts 15 and 16, which are welded with the strengthening bars 19 to the inside and outside of the drum, in the region of these channels 21.

Each contact bar is formed from two cathode rods which are arranged coaxially, and are electrically connected, each rod having a circular cross-section.

To agree with the cross-section shape of the cathode rods, each strengthening rod 19 has a partially circular recess in which the two coaxially-running cathode rods 18 are mounted, and from which part of their surface projects (is exposed) to make contact with the shaped parts to be galvanized.

The heart shape of the pendulum drum 12 is formed by the four wall parts 15 and 16, which are connected together by three strengthening bars 19. The two adjacent partially circular (annular) shaped wall parts 15 I represent the floor region of the drum 12, and to each wall part 15 the curved part of a wall part 16 is connected to rectilinear regions of the wall parts forming the opening 14 at the top.

The ends of the strengthening bars 19 fit into recesses 22, which extend part way through the ends 20.

The wall parts and 16 are braced on the inside of the drum by ribs 23, and in the region of the filling and emptying opening 14, by exterior bars 24.

The wall parts 15 and 16, the strengthening bars 19, the end walls 20 and the stiffening ribs 23, as well as stiffening bars 24 of the pendulum drum 12, are of plastics material such as polypropylene, and the wall parts 15 and 16 pre-shaped while hot.

The wall parts 15 and 16 extend in over the entire length of the drum; they can, however, be formed from several parts, extending over the longitudinal direction of the drum.

Each contact bar, which runs the entire length of the drum, and is formed from two coaxially arranged cathode rods 18, mounted in a common bearing receptacle 17 of the strengthening profile 19, is held detachably in the drum 12, in the central longitudinal region or elsewhere, by a bridge 25 of non-conducting material; this bridge 25, consisting of plastics material, covers a joint between the two coaxial cathode rods 18, the joints including a spigot 18a of the adjacent contact bar. The bridge is fixed detachably according to position, by a bolt 26 which passes through the strengthening bar 19, and is secured by a nut screwed onto the outside of the drum, in the connection region of two cathode rods 18.

Each cathode rod 18, at its end away from the plastics bridge 25, passes sealingly through the end wall 20 of the drum, and is connected to a contact part 32 which is covered by an insulation layer 28 which is insulated from the end wall 20 of the drum and fastened detachably to the outside of it; there is a terminal for an electric current supply line 31.

The contact part 32 is formed from a metal plate 29, with the metal terminal 30 fastened on it, and an insulation layer 28, preferably of rubber, which surrounds this metal core 29 and the connection piece 30 on all sides up to the points of contact with the cathode rods 18 and the current cable 31 (compare FIGS. 4 and S).

The cathode rod 18 is fastened to the contact part 32 by a threaded end 33, and is detachably connected to the contact part 32 by a nut 35 which is screwed on to the outside of the end 33. The nut is covered by an insulation cap 34; the contact connection between cathode rod 18 and contact part 32 takes place inside the bore of the metal core 29, which accepts the threaded end 33.

The contact plate 32 provided on the outside of each end wall 20 of the drum extends part-circularly around the bearing axis 13 of the drum, and is detachably fastened by means of several screws 36 which penetrate through bore-holes covered by the insulation layer 28, and by nuts 37, to the end wall 20 of the drum.

The terminal 30 extends from an end region of the partially circular contact part 32, and has a hole 38 to receive a contact end 39 of the conductor 31, which is insulated against moisture. The conductor end 39 is connected detachably to the terminal 30 by a nut 41 which is screwed onto the end 39 and which is covered by an insulation cap 40. All cathode rods 18 are supplied with current by this terminal 30, one of which is provided on each contact part 32.

The carrying frame 10 is formed from two carrying plates 43 which are connected together by tie rods 42, and accept the stub shafts 13 of the drum. On this carrying frame 10 is mounted a propulsion device 44, a

driving motor with gearing, which is connected, by its driving pinion 45 via an intermediate wheel 46 to a toothed wheel 47 which is fastened to one end of the drum. The motor drives the pendulum drum 12 with a rocking (to and fro) movement.

The carrying frame 10 has two carrying plates 43 with two pins 48 with which the carrying frame 10 and its pendulum drum 12 can be suspended as a unit in the forks 49 of a treatment bath container 50, a filling or emptying container, a drying kiln, a transport device 51 or the like.

Each carrying frame plate 43 has a conductor rail 52 to which the current conductor 31, which leads to the contact part 32, is connected. The current supply for the pendulum drum 12 is derived from a low voltage source with a high current output (e.g., 750 amp. at 15v). The current is brought to the conductor rail 52, in each case via a current supply line 63 which is connected to the forks 49, and the pins 48 enclosed therein, from which the current reaches the cathode rods 18 via the line 31 connected to it (and via the insulated contact part 32).

The current supply for the propulsion motor 44 is separately derived from a connector 53 which is located at one end of the frame 10. This connector 53, upon insertion of the drum 12 in the bath container 50, is connected to a complementary part 54 which is arranged on the container three-phase current is used for the propulsion motor 44, the current being fed through a line 64 of the counter-contact device 54.

On the front of the drum facing the gear motor 44, there is a plastic index ring 55 surrounding the bearing 13, to which several metallic switching plates 56, 57 and 58 are fastened, which co-operate with a commutator 59 fastened detachably on the support 50 and 51, for control of the drum 12 between its two end positions, and the filling or emptying position. The commutator has an index ring 55 on which there are five metal plates 56, 57 and 58, which are spaced from one another, and at three different diameters, two approximately diametrically opposite metal plates 56 of which are arranged on the smallest diameter, and serve to limit the extreme pivotal positions of the drum. Two further metal plates 57 which are also approximately diametrically opposite, and are displaced against the direction of rotation of the drum in relation to the metal plates 56, represent security contacts, and are situated at the largest diameter.

A metal plate 58, which is arranged on the medial diameter between the four previous contacts, forms a contact for the location of the pendulum drum 12 in its emptying position.

The commutator 59 has two fixed brushes 60 and 61, which are spaced apart, the brush 60 being on the diameter of the metal plates 56, and the brush 61 on the diameter of the contact 57. These brushes 60 and 61 are so located that in the event of their touching one of the contacts 56 or 57, the motor 44 for rotating the drum is switched off and reversed, or switched right off in an emergency.

If the metal plate 56 is contacted by the brush 60, the drive of the drum in one direction is terminated, and the motor 44 is reversed to produce the opposite rotation of the drum. It the brush 60 fails, or if one of these metal plates 56, through a defect in the brush 60 overruns the latter, the metal plate 57 encounters brush 61 after a small further rotation of the drum 12, and the rotation of the drum is arrested.

To empty the drum 12, the latter is rotated until the excitation plate 58 is situated between the two brushes 60 and 61, this brings the motor to a standstill.

The pendulum drum 12, is divided into two or more chambers by one or more dividing walls 62. The dividing walls 62 are removably inserted in the drum 12, and can be pushed along the longitudinal direction of the drum into the desired position; they can be fixed in position by fastening means, such as screws, clamps or the like. When the separating walls 62 are removed, long work pieces can be treated. The shiftable dividing walls 62 make possible the formation of chambers of optional dimensions.

The dividing walls 62 enable workpieces of various types to be treated separately in the drum 12.

The plating device described can be incorporated in a plating installation having several stations arranged one after the other.

We claim:

1. A galvanizing device comprising, in combination:

a. a first, fixed frame;

b. a drum having a perforated wall with a filling opening therein, a pair of end walls secured to said perforated wall, journal means integral with said ends walls and contact rods integral with said perforated wall;

c. a second, movable frame supporting said drum for oscillating movement to and fro about the longitudinal axis thereof; motor means for driving said drum; and

e. commutator means adapted to be connected to a source of electrical power and electrically coupled to said motor means for controlling the energization of said motor means, said commutator comprising:

l. a plurality of metallic plates secured to one of said end walls of said drum; and

2. metallic brush means mounted on said first frame in opposition to and arranged for selective contact by said metallic plates whereby the drive of said motor means is periodically interrupted and the direction of drive of said motor means is reversed.

2. The galvanizing device in accordance with claim 1 wherein said metallic plates are angularly spaced apart from each other and are located on three different diameters, said brush means being spaced apart from each other and positioned coincidentally with two of said diameters.

3. The galvanizing device in accordance with claim 2 wherein said diameters are concentric and wherein two of said plates are on said innermost diameter, two others of said plates are on said outermost diameter and one other of said plates is on said median diameter, said brush means being arranged for contact with said plates on said innermost and said outermost diameters.

4. The galvanizing device in accordance with claim 3 wherein said plates on said innermost and said outermost diameters are approximately diametrically opposed.

5. The galvanizing device as recited in claim 1, in

which said tperipheral wall is comprised of two parts that are par -circular1n cross-section, and two which in cross-section have one curved region and one rectilinear region connected thereto, the two partially circular wall parts forming the floor of said drum and the two other wall parts forming the lateral region, the edges of the rectilinear wall parts defining the filling opening.

6. The galvanizing device as recited in claim 1, further including strengthening bars having channels for receiving said wall parts, each of said bars also including a recess for mounting a respective contact rod and recesses in said end walls of said drum for receiving said bars.

7. The galvanizing device as recited in claim 1, wherein each said contact rod extends over the entire length of the drum, and comprises two cathode rods arranged end to end, a bridge of non-conducting material in the central region of said drum for holding said two cathode rods together, a contact part connected to each said rod and detachably fastened to the outside of an end wall of said drum, a terminal for an electric current supply line connected to said contact part, and an insulation layer enveloping said contact part.

8. The galvanizing device as recited in claim 7, wherein said contact part is a curved metal plate having a metal terminal thereon, an insulation layer of rubber therein which covers said plate and said terminal on all sides, a threaded end on each said cathode rod connecting said rod to said contact part and fastener means for said plate, said fastener means penetrating through bore holes defined by said insulation layer.

9. The galvanizing device as recited in claim 8, wherein said terminal is fitted on one end of said curved plate and an insulated fastener connecting said current supply line to said terminal.

10. The galvanizing device as recited in claim 1, wherein said journal means comprises two endmounted stub shafts on and forming pivots for said drum, bearings on said second frame for receiving said stub shafts and a toothed driving wheel on said drum, said motor including a pinion for driving said toothed wheel.

11. The galvanizing device as recited in claim 10 further comprising a current line and a current supply rail, said bearings connecting said rails to a low voltage source of high current output.

12. The galvanizing device as recited in claim 1 further comprising at least one movable and fixable dividing wall located in said drum, said dividing wall forming chambers which are adjustable in size, and separated from one another. 

1. A galvanizing device comprising, in combination: a. a first, fixed frame; b. a drum having a perforated wall with a filling opening therein, a pair of end walls secured to said perforated wall, journal means integral with said ends walls and contact rods integral with said perforated wall; c. a second, movable frame supporting said drum for oscillating movement to and fro about the longitudinal axis thereof; d. motor means for driving said drum; and e. commutator means adapted to be connected to a source of electrical power and electrically coupled to said motor means for controlling the energization of said mOtor means, said commutator comprising:
 1. a plurality of metallic plates secured to one of said end walls of said drum; and
 2. metallic brush means mounted on said first frame in opposition to and arranged for selective contact by said metallic plates whereby the drive of said motor means is periodically interrupted and the direction of drive of said motor means is reversed.
 2. metallic brush means mounted on said first frame in opposition to and arranged for selective contact by said metallic plates whereby the drive of said motor means is periodically interrupted and the direction of drive of said motor means is reversed.
 2. The galvanizing device in accordance with claim 1 wherein said metallic plates are angularly spaced apart from each other and are located on three different diameters, said brush means being spaced apart from each other and positioned coincidentally with two of said diameters.
 3. The galvanizing device in accordance with claim 2 wherein said diameters are concentric and wherein two of said plates are on said innermost diameter, two others of said plates are on said outermost diameter and one other of said plates is on said median diameter, said brush means being arranged for contact with said plates on said innermost and said outermost diameters.
 4. The galvanizing device in accordance with claim 3 wherein said plates on said innermost and said outermost diameters are approximately diametrically opposed.
 5. The galvanizing device as recited in claim 1, in which said peripheral wall is comprised of two parts that are part-circular in cross-section, and two which in cross-section have one curved region and one rectilinear region connected thereto, the two partially circular wall parts forming the floor of said drum and the two other wall parts forming the lateral region, the edges of the rectilinear wall parts defining the filling opening.
 6. The galvanizing device as recited in claim 1, further including strengthening bars having channels for receiving said wall parts, each of said bars also including a recess for mounting a respective contact rod and recesses in said end walls of said drum for receiving said bars.
 7. The galvanizing device as recited in claim 1, wherein each said contact rod extends over the entire length of the drum, and comprises two cathode rods arranged end to end, a bridge of non-conducting material in the central region of said drum for holding said two cathode rods together, a contact part connected to each said rod and detachably fastened to the outside of an end wall of said drum, a terminal for an electric current supply line connected to said contact part, and an insulation layer enveloping said contact part.
 8. The galvanizing device as recited in claim 7, wherein said contact part is a curved metal plate having a metal terminal thereon, an insulation layer of rubber therein which covers said plate and said terminal on all sides, a threaded end on each said cathode rod connecting said rod to said contact part and fastener means for said plate, said fastener means penetrating through bore holes defined by said insulation layer.
 9. The galvanizing device as recited in claim 8, wherein said terminal is fitted on one end of said curved plate and an insulated fastener connecting said current supply line to said terminal.
 10. The galvanizing device as recited in claim 1, wherein said journal means comprises two end-mounted stub shafts on and forming pivots for said drum, bearings on said second frame for receiving said stub shafts and a toothed driving wheel on said drum, said motor including a pinion for driving said toothed wheel.
 11. The galvanizing device as recited in claim 10 further comprising a current line and a current supply rail, said bearings connecting said rails to a low voltage source of high current output.
 12. The galvanizing device as recited in claim 1 further comprising at least one movable and fixable dividing wall located in said drum, said dividing wall forming chambers which are adjustable in size, and separated from one another. 